It's been my observation over the past few years, and particularly over the past few months, that a similar law applies to any conversation about radical honesty within a relationship. I've participated in quite a few entirely separate conversations on the subject of communication on entirely different forums with entirely different people, and in nearly every case, someone somewhere has argued against the notion that a person ought to be able to share anything at all with a romantic partner in the same way.
So I'd like to propose a new law, which states: As an online discussion about communication or radical honesty grows longer, the probability that someone will say "Well, you don't tell your partner every time you take a shit, do you?" approaches 1.
I'd further like to propose a corollary which says that the person making the comment about excretory functions, by making that statement, has demonstrated conclusively that he or she does not understand the value of open communication. Namely, that it's not about telling your partner every minute detail of your life, it's about being ABLE to talk to your partner about any subject whatsoever, without the feeling that there are certain topics that you Dare Not Broach for fear of Bad And Dramatic Things.